Before I start, let me say that I'm not telling you how to draw. You draw however you're gonna draw, HOWEVER look to real life for what you're drawing. The problem with the dinner plate eyed manga character is that generally, that feature that we're most drawn to, that takes up most of the face is empty and dull.
Study your own facial expressions in the mirror. Carefully note what your brows do, how your mouth moves. This will help you greatly.
This book can be found at pretty much any chain bookstore. Sit a while and give it a read. It will read very quickly and you can learn just what I mean, using your own face and your friends as reference.